<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8" />
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta name="viewport"
    content="width=device-width, initial-scale=1, maximum-scale=1,minimum-scale=1, user-scalable=no" />
  <title>圆形</title>
  <link rel="shortcut icon" href="./favicon.ico" type="image/x-icon" />
</head>

<body>
  <canvas id="canvas" width="1000" height="1000"></canvas>
</body>
<script>
  let canvas = document.querySelector("#canvas");
  let ctx = canvas.getContext("2d");
  ctx.arc(100, 200, 100, 0, 2 * Math.PI);
  ctx.fillStyle = "pink";
  ctx.fill();
  ctx.stroke();
</script>

</html>